JPS607466Y2 - Trimmer capacitor for tuner - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of an electronically tuned tuner used in televisions and the like.

The LJHF electronically tuned tuner used for television is
A box-shaped metal case is partitioned with shield plates to create small chambers, and electronic components such as transistors and resistors are placed inside these chambers, as well as tuning elements for distributed constant circuits.

FIG. 1 is a perspective view showing the inside of a conventional UHF electronic tuning tuner. In the figure, 1 is a metal case, 2 is a shield plate that partitions the inside of the metal case 1, and 3 is a metal case 1 and a shield plate 2. The line rod 4 stored in the formed small chamber is a capacitor connected between the line rod 3 and the bottom wall 1a of the metal case 1.
It constitutes a wavelength resonator.

5 is a trimmer piece fixed to the tip of the line rod 3, 6 is a trimmer piece installed upright on the bottom wall 1a, and is arranged opposite to the trimmer piece 5, and the opposing distance and opposing area are This is to finely adjust the resonant frequency by changing the capacitance of the capacitor that makes up the resonant circuit.

By the way, one trimmer piece of the trimmer capacitor of the above-mentioned IJHF electronic tuner is attached to the bottom wall 1a of the metal case which serves as the ground.

Recently, as tuners have become smaller, metal cases have also become much smaller, but the trimmer capacity cannot be reduced either.

Therefore, the size of the trimmer piece becomes relatively large,
The adjustable range of the trimmer, that is, the physical distance it moves, becomes smaller, and the range of variable capacity becomes very narrow.

Further, since the trimmer piece 6 must be handled as an independent part, parts management is also difficult, and manufacturing and installation costs are also increased.

This invention is a new invention that improves the above-mentioned drawbacks of the conventional technology.The purpose of this invention is to simplify the structure of the trimmer capacitor as much as possible in a tuner in which a trimmer capacitor is provided in the resonant circuit, and to increase the amount of capacitance change of the trimmer capacitor. The aim is to provide a structure that allows for

Next, one embodiment of the present invention will be described in detail using the drawings.

In the perspective view shown in FIG. 2, 1 is a metal case, 2a and 2b are shield plates, 3 is a line rod, 4 is a capacitor,
5 is a trimmer piece.

Reference numeral 7 denotes a trimmer piece cut and raised in an L-shape in the direction of the trimmer piece 5 from the shield plate 2b.As shown in FIG.
By changing the interval between and 7, the capacitance of the trimmer capacitor is changed.

FIG. 4 is a perspective view showing another embodiment of the trimmer capacitor.

This embodiment has two cuts 7 in the root part 8 of the trimmer piece 7.
b, 7c are provided, and the trimmer piece 7 swings in the front-rear direction (arrow A-A direction) as in the previous embodiment, and the trimmer piece 5
The facing distance can be changed, and in addition, the facing area can also be changed by rotating in the direction of arrow B-B.

In addition, in the second embodiment, a configuration may be adopted in which the notch is provided only at one end.

FIG. 5 is a perspective view showing the third embodiment, and in the figure, 7d
is a slit provided in the trimmer piece 7 in the vertical direction.

In this embodiment, the capacitance of the trimmer capacitor is changed by bending one or more of the trimmer strips 7e, 7e, etc. divided by the slit 7d, and partially changing the distance facing the trimmer strip 5. It is also.

Note that a structure in which the trimmer piece 7 shown in FIG. 4 is provided with a slit 7d may also be adopted.

The present invention is similar to the above embodiment. It can be applied not only to a 4-wavelength resonator but also to an 11-wrinkle length resonator.

Further, the trimmer piece provided on the line rod does not have to be integrated with the line rod, and can be removed.

As explained in detail above, according to the present invention, one of the trimmer pieces constituting the trimmer capacitor can be constructed by simply cutting and raising the shield plate, eliminating the need for fixing the trimmer piece to the shield plate, etc. The structure is extremely simple, and there is no need to handle the trimmer piece as a single component as in the past, so parts management is also easy.

Moreover, by omitting parts, the distance between the trimmer piece attached to the line rod and the shield plate can be increased, so even if the tuner structure is made smaller, the variable capacitance range of the trimmer capacitor can be increased. This has many effects, such as making it easier to adjust the tuner.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing a conventional tuner, FIG. 2 is a partially cutaway perspective view showing an embodiment of the present invention, FIG. 3 is a side view of the trimmer for explaining the operation, and FIG. Figure and 5th
The figure is a partial perspective view showing another embodiment. In the figure, 1 is a metal case, 2a, 2b are shield plates, 3 is a line rod, 4 is a capacitor, 5, 6.7 are trimmer pieces,
7b and 7c are notches, 7d is a slit, 7e is a trimmer strip, and 8 is a root.

Claims (1)

[Scope of utility model registration request] Consisting of one trimmer piece formed by cutting and raising a part of a shield plate that partitions the inside of a metal case, and the other trimmer piece facing this trimmer piece and fixed to the tip of a line rod, A trimmer capacitor for a tuner, characterized in that the capacitance of the capacitor is changed by changing the distance or opposing area between one cut and raised trimmer piece and the other trimmer piece.